The present invention relates to a protective helmet, in particular for motorcyclists, of the type comprising a first outer visor to intercept the viewing aperture of the helmet, mounted rotatably on said helmet, and a second visor, preferably for partly shielding the sun's rays, mounted rotatably on the cap of the helmet, in an internal position with respect to the outer visor.
It is known in the art to provide protective helmets for motorcyclists with an additional visor for partly shielding the sun's rays which overlaps in part the visor, usually transparent, intercepting the viewing aperture of the helmet. Actuation of said additional visor is mechanically separate from actuation of the interception visor and must allow the user to engage or disengage said additional visor with or from the field of vision of said user, separately from the position taken by the transparent visor.
The Italian patent IT 1.177.250 by the applicant Bayerische Motoren Werke Aktiengesellschaft (BMW) describes a similar protective helmet for motorcyclists, in which the additional visor for partly shielding the sun's rays is mounted, with at least a degree of freedom, on the cap of the helmet so that it is in an internal position with respect to the transparent visor. The particular constraint of said additional visor inside the cap allows said additional visor to move between a position partly intercepting the viewing aperture of the helmet and a position disengaged therefrom, wherein said additional visor is housed inside a seat specifically provided in said cap.
The internal configuration of the addition visor with respect to the transparent visor allows greater protection thereof against external agents and also prevents the additional visor from being accidentally actuated by the user. In this way, the additional inner visor does not obstruct the aerodynamic function of the outer visor and, if said inner visor is of the type for partly shielding the sun's rays, it acts only as an anti-dazzle visor, without necessarily having to protect the user from other external agents.
The European patent application EP-A-1 393 642 by the applicant Osbe Srl relates to a protective helmet comprising an addition visor for partly shielding the sun's rays, positioned internally with respect to the transparent visor. This additional visor described in the Osbe application is hinged at the side to the cap and is provided with a kinematic actuation mechanism comprising a tie constrained in rotation to one end of the inner visor and constrained, at the other end thereof, to a manual control, positioned on the outside of the cap of the helmet.
The Osbe application does not provide for removable coupling of the additional inner visor with the cap, but rather the side ends of the inner visor are constrained to two coaxial pins, positioned on the inner walls of the side portions of the viewing aperture of the cap of the helmet.
This means that any operations to remove and mount the inner visor, necessary for cleaning, maintenance or replacement thereof, are particularly complicated, requiring specific tools and the removal of several portions of the helmet.
The international patent application WO 2006/037295 by the applicant Schuberth Engineering AG describes a protective helmet for motorcyclists wherein a sun visor is constrained, internally with respect to the transparent visor intercepting the viewing aperture of the helmet, using projections, or followers, integral with the side ends of said sun visor, with relative circular guides integral with the cap of the helmet. The sun visor of this Schuberth application is therefore not constrained to any pin inside the cap and rotation thereof is permitted, and limited, by said circular guides. Rotation of the sun visor described in WO 2006/037295 is controlled by a manually actuated slider, constrained in translation to the cap, through some ties that connect the slider to one end of said sun visor.
Although allowing a reduction of the overall dimensions of the sun visor in the cap and allowing, with modification of the curvature radius of the circular guides, the centre of instantaneous rotation of the sun visor to be positioned as desired, in the Schuberth solution the projections of the sun visor inserted in the circular guides must support all the loads to which the sun visor is subjected, above all during actuation thereof, resulting in possible problems of wear and premature deterioration.
Moreover, as the assembly of the sun visor inside the Schuberth helmet does not provide for any type of centering, it is made difficult by misalignment, which in fact can take place during operations to mount one or other end of this inner visor, of the projections of the sun visor with respect to the two circular guides.
Finally, the practical embodiment of the Schuberth solution proves to be complex and therefore with possible drawbacks linked to the reliability and functionality of the relative helmet.